Inflatable airbag devices, which are now more commonly referred to in the art as Supplementary Restraint Systems (SRS), Air Cushion Restraint Systems (ACRS), or Supplemental Inflatable Restraint (SIR) Systems, are originally equipped in almost all present day automotive vehicles. Airbag devices are generally located in the passenger compartment of automotive vehicles, and act as a selectively deployable cushion capable of attenuating kinetic energy.
Traditional airbag devices comprise an inflatable airbag module stored either behind the vehicle instrument panel (e.g., for passenger-side airbags), or mounted to the steering wheel hub (e.g., for driver-side airbags). A plurality of sensors or similar devices is strategically located to detect the onset of a predetermined event. The sensor(s) responsively activates an inflation device, internally located in the airbag module, to produce a flow of inflating gas into an inflatable flexible membrane (i.e., an airbag cushion), also located within the airbag module. This causes the airbag cushion to be deployed in a rearward direction within the vehicle passenger compartment.
Many automotive vehicles are currently being designed with a supplemental inflatable restraint system located on a downward and forwardly inclined portion of the instrument panel, commonly identified as the “knee bolster”. The knee airbag can be extended so as to restrain the lower half of the occupant. During a predetermined event, the knee airbag is inflated, traditionally passing or breaking through a rearward-facing, exterior show surface of the knee bolster, in a manner similar to that described above.